The document discusses plotting the electric field between two parallel plates with opposite charges. It uses ListPlot3D to plot the electric potential V between the plates, showing the potential drops from +1 V on one plate to -1 V on the other. It also uses ListPlot3D to plot the x and y components of the electric field, Ex and Ey. Finally, it visualizes the electric field vectors between the plates using ListVectorPlot and ListStreamPlot with Ex and Ey.